Interoception
Interoception is the sense of the internal functioning of the body. An interoceptor is any sense organ or sensory receptor which responds to stimuli within the body signalling for example hunger, thirst, nausea etc These include: * Pulmonary stretch receptors are found in the lungs and control the respiratory rate. * Peripheral chemoreceptors in the brain monitor the carbon dioxide and oxygen levels in the brain to give a feeling of suffocation if carbon dioxide levels get too high.http://science.howstuffworks.com/environmental/life/human-biology/lung3.htm * The chemoreceptor trigger zone is an area of the medulla in the brain that receives inputs from blood-borne drugs or hormones, and communicates with the vomiting center. * Chemoreceptors in the circulatory system also measure salt levels and prompt thirst if they get too high (they can also respond to high sugar levels in diabeticshttp://healthguide.howstuffworks.com/thirst-excessive-dictionary.htm). * Cutaneous receptors in the skin not only respond to touch, pressure, and temperature, but also respond to vasodilation in the skin such as blushing. * Stretch receptors in the gastrointestinal tract sense gas distension that may result in colic pain. * Stimulation of sensory receptors in the esophagus result in sensations felt in the throat when swallowing, vomiting, or during acid reflux. * Sensory receptors in pharynx mucosa, similar to touch receptors in the skin, sense foreign objects such as food that may result in a gag reflex and corresponding gagging sensation. * Stimulation of sensory receptors in the urinary bladder and rectum may result in sensations of fullness. * Stimulation of stretch sensors that sense dilation of various blood vessels may result in pain, for example headache caused by vasodilation of brain arteries. Neuroscience Interoceptive awareness The right anterior insula aids interoceptive awareness of body states, such as the ability to time one's own heart beat. Moreover, greater right anterior insular gray matter volume correlates with increased accuracy in this subjective sense of the inner body, and with negative emotional experience. It is also involved in the control of blood pressure, particularly during and after exercise, and its activity varies with the amount of effort a person believes they are exerting. The insular cortex also is where the sensation of pain is judged as to its degree. Further, the insula is where a person imagines pain when looking at images of painful events while thinking about them happening to one's own body. Those with irritable bowel syndrome have abnormal processing of visceral pain in the insular cortex related to dysfunctional inhibition of pain within the brain. Another perception of the right anterior insula is the degree of nonpainful warmth or nonpainful coldness of a skin sensation. Other internal sensations processed by the insula include stomach or gastric distension. A full bladder also activates the insular cortex. One brain imaging study suggest that the unpleasantness of subjectively perceived dyspnea is processed in the right human anterior insula and amygdala. The cerebral cortex processing vestibular sensations extends into the insula with small lesions in the anterior insular cortex being able to cause loss of balance and vertigo. Other noninteroceptive perceptions include passive listening to music, laughter and crying, empathy and compassion,http://ccare.stanford.edu/node/89 and language. See also *Sensation References Category:Senses